There's been an ongoing debate about whether communities should combine or stay separate. Both have significant disadvantages and advantages:
Combine:
- Network effects. Smaller communities become viable if they pool together their userbase. Communities with more people (up to a point!) are generally more useful and fun.
- Discoverability. Right now, I might stumble on a 50 subscriber community and not realize everyone has abandoned it for the lively 500 subscriber community somewhere else, maybe with a totally different name.
Separate:
- Redundancy. If a community goes down, or an instance is taken down, people can easily move over.
- Diffusion of political power. Users can choose a different community or instance if the current one doesn't suit them. Mods are less likely to get drunk on power if they have real competition.
This isn't an exhaustive list, but I just want to show that each side has significant advantages over the other.
Sibling communities:
To have some of the advantages of both approaches, how about we have official "sibling communities"? For example, sign up for fediverse@lemmy.world and, along the top, it lists fediverse@lemmy.ml as a sibling community.
- When you post, you have an easily accessible option to cross-post automatically to all sibling communities. You can also set it so that only the main post allows comments, to aggregate all comments to just one post, if that's desirable.
- The UI could detect sibling cross-posts and suppress multiple mentions of the same post if you're subscribed to multiple sibling communities, maybe with a "cross-sibling post" designation. That way it only shows up once in your feed.
- Both mod teams must agree to become siblings, so it can't be forced on any community.
- Mods of either community can also decide to suppress the cross post if they feel it's too spammy or not suitable for cross discussion.
- This allows you to easily learn about all related communities without abandoning your current one. This increases the network effects without needing to combine or destroy communities.
Of course, this could be more informal with just a norm to sticky a post at the top of every community to link to related communities. At least that way I know of the existence of other communities. I personally prefer the official designation so that various technologies can be implemented in the ways I mentioned.
They are two separate posts, it's just cross-posting won't flood your instances "all" feed. They would still appear as a post in /c/London and one in /c/NewYork with separate comment threads
In the Reddit apps that had multi-sub functionality then I believe they were user created but this is a brave new world and we don't have to do it that way. People or instances or communities could create multi-communities and people could subscribe to them so only a central file would be updated. If it stopped being updated or was too broad or too specific, it could be forked. I wonder if that could even be rolled into a possible future wiki system as it need only be a text-based file listing the communities.
So, if cross-posts are not showing up in my feed, then I have to actively look for cross-posts separately in the communities? How would I even know they exist? That's still not what I want. In other words, there are two kinds of cross-posts: (1) redundant posts to overlapping demographics. I don't want to see more than one of these. (2) commentary cross-posts. I want to see these as separate posts.
Sibling communities would hide (1) and not (2).
I like that you're imagining new ways to do this. That's what I'm trying to do too. This brave new world of community created multi-communities honestly sounds a lot like sibling communities to me. There's the question of who is making the multi-communities, and to me the natural response is "the communities themselves". There's less user friction if a community is just already affiliated with a bunch of other communities voluntarily.